The sahara desert has an area of approximately 9 400 000 km^2. while estimates of its average depth vary, they center around 150 m. one cm^3 holds approximately 8 000 grains of sand. a. approximately how many grains of sand are in the sahara desert? b. what fraction of the sahara is made by 1 grain of sand? c. a small dump truck can carry approximately 20.5 m^3 of sand. suppose a long line of dump trucks were to dump a load of sand every 30 seconds. how many years would it take to re-create the sahara desert?

What is a possible solutions of the x> 3?

If square root x = -7, then x= -49 true or false

Ariana starts with 100 milligrams of a radioactive substance. the amount of the substance decreases by 20% each week for a number of weeks, w. the expression 100(1−0.2)w finds the amount of radioactive substance remaining after w weeks. which statement about this expression is true? a) it is the difference between the initial amount and the percent decrease. b) it is the difference between the initial amount and the decay factor after w weeks. c) it is the initial amount raised to the decay factor after w weeks. d) it is the product of the initial amount and the decay factor after w weeks.